William Gray Purcell (July 2, 1880 – April 11, 1965) was a Prairie School architect in the Midwestern United States. He partnered with George Grant Elmslie, and briefly with George Feick. The firm of Purcell & Elmslie produced designs for buildings in twenty-two states, Australia, and China. The firm had offices in Minneapolis, Minnesota; Chicago, Illinois; Philadelphia, Pennsylvania; and Portland, Oregon.